The story of the Donner Party looms large in American folklore. On April 14, 1846, this group of immigrants embarked on a 2,500-mile journey from Springfield, Ill., to San Francisco -- but, because of bad timing, terrible advice and even worse weather, only a fraction of them reached their final destination. The Donner Party has become legendary because of the extremity of the situation and also because of what the group did to survive a hellish winter in the Sierra Nevada mountains. As food became more and more scarce, and as members of the group began dying from starvation and illness, the rest of the party resorted to cannibalism as a means of survival.

This aspect of the Donner Party's story has been a grotesquely fascinating part of the American consciousness since it happened during the height of westward expansion. History buffs are still intrigued because of our forebearers' will to survive and the risks they took. Today, it's easy to forget the hardships that American trailblazers had to endure -- we don't necessarily think about the possibility of having to devour our fellow travelers when we step on the train for our morning commute or take our seat on a cross-country flight.

But the story of the Donner Party is a frightening reminder of what could be. Were it not for a few wrong turns, a bit of bad directions and a winter storm the likes of which had never been seen, the Donner Party would have been an unremarkably successful wagon train. But as it happened, it became a lesson of what can happen when everything goes wrong, a cautionary tale of manifest destiny and an unforgettable tragedy in American history. How did the Donner Party wind up isolated, in such desperate circumstances?

In the early 1800s, the United States witnessed the birth of the railroad industry and along with it, dramatic changes in American society and business. What was life like before and after the railroads?